Most of our home network devices are named after characters in Tenchi Muyo! (it's a long story) - I usually try and choose hostnames with some kind of "nod" to where the characters resemble the device in some way. For example, my Eee 701SD netbook is "sasami" (small and cute), our nettop PC is "washu" (OK, the naming/characteristics thing fell down a bit there), and our Synology NAS box/home server is "tenchi" (centre of the household!).
Any fans of the series here, may guess what I'm planning to call my first RasPi: what else, but "ryo-ohki"? (Haven't decided whether to include the hyphen, for compatibility reasons, but it just reads better than "ryoohki" to me.)
Also, if I ended up buying a second RasPi, I think I'd have to call it "ken-ohki"...
Raspberry Pi Model 3B+ (2019) ("ayeka") - CentOS
Raspberry Pi Zero W (2018) ("mass") - Raspbian
Raspberry Pi Model B (1st-gen - 2012) ("ryo-ohki") - Arch Linux ARM